The problems with the Crusader weapons system were that it was way over budget ,too large/heavy for the majority of the roads/tunnels/bridges in over 85% of Europe were it was supposed to be first deployed & that it is slower than the weapon that it was to replace . On the modern battle field that combination gets you killed.
A redesign reduced the weight of the Crusader from 60t to around 40t, and gave it a road speed of over 60 km/h. Recall that much of the same sort of criticism was aimed at the Main Battle Tank- too heavy, too expensive, unneccessary. But who would want to be without the Abrams today?
The Palladin is an older system. Crusader was designed with a new gun tube and advanced fire control to put a lot of metal on target in a big hurry. It can be reloaded and refueled faster. Something like it will eventually replace older pieces if we intend to retain our technological advantage on the battlefield.
FN-FAL .308s rule, btw.